| USD ($) $ in Thousands | Jun 30, 2026 | Mar 31, 2026 | Sep 30, 2025 | Jun 30, 2025 | Mar 31, 2025 | Sep 30, 2024 | Jun 30, 2024 | Mar 31, 2024 | Sep 30, 2023 | Jun 30, 2023 | Mar 31, 2023 | Sep 30, 2022 | Jun 30, 2022 | Mar 31, 2022 | Sep 30, 2021 | Jun 30, 2021 | Mar 31, 2021 | Sep 30, 2020 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Operating activities | ||||||||||||||||||
Net income | $ 1,065,962 | $ 876,402 | $ 476,748 | $ 328,572 | $ 217,717 | $ 149,341 | $ 135,570 | $ 106,071 | $ 73,439 | $ 27,872 | $ 19,151 | - | ||||||
Net loss | - | - | - | - | - | - | - | - | - | - | - | (123,875) | ||||||
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] | ||||||||||||||||||
Depreciation and amortization | 8,220 | 6,765 | 5,975 | 6,530 | 6,622 | 8,087 | 8,056 | 8,438 | 8,663 | 8,399 | 8,320 | 5,942 | ||||||
Stock-based compensation | 265,209 | 201,592 | 172,318 | 159,971 | 155,339 | 142,425 | 141,764 | 125,651 | 114,380 | 114,201 | 114,714 | 140,308 | ||||||
Change in fair value of warrants | - | - | - | - | - | - | - | - | - | - | - | - | ||||||
Deferred income taxes | - | - | - | - | - | - | - | - | - | - | - | (17) | ||||||
Noncash operating lease expense | - | - | - | - | - | 9,602 | 10,073 | 12,366 | 12,086 | 11,888 | 10,836 | 9,884 | ||||||
Unrealized and realized (gain) loss from marketable securities, net | (62,242) | - | 5,457 | (11,140) | 10,688 | 5,979 | 7,688 | 12,354 | 732 | 2,570 | 8,508 | 59,379 | ||||||
Noncash consideration | - | - | (7,612) | (7,128) | (17,313) | (8,305) | (14,577) | (11,907) | (14,686) | (20,166) | - | - | ||||||
Unrealized loss from marketable securities | - | - | - | - | - | - | - | - | - | - | - | - | ||||||
Other operating activities | (31,623) | (53,959) | (10,700) | 23,002 | 3,531 | 30,203 | (4,314) | (6,774) | 4,489 | (6,475) | (11,342) | 6,022 | ||||||
Changes in operating assets and liabilities: | ||||||||||||||||||
Accounts receivable, net | (72,828) | (360,973) | (259,476) | (28,542) | (134,959) | (13,388) | (176,427) | (121,884) | (46,089) | (113,035) | (628) | (78,852) | ||||||
Prepaid expenses and other assets | (102,968) | 49,062 | 57,650 | (48,037) | 40,730 | (16,773) | (22,173) | 19,399 | (1,166) | (882) | 1,973 | 30,571 | ||||||
Accounts payable and accrued liabilities | 7,309 | 80,788 | 42,380 | 25,807 | 22,395 | - | - | - | - | - | - | - | ||||||
Other assets | - | - | - | - | - | (1,515) | 2,046 | 3,525 | 5,426 | 1,066 | (4,551) | 2,403 | ||||||
Accounts payable | - | - | - | - | - | (45,662) | 29,563 | 23,809 | 6,670 | 864 | (39,921) | 4,820 | ||||||
Accrued liabilities | - | - | - | - | - | 72,697 | (11,443) | (19,105) | (11,228) | 9,509 | 4,271 | (29,678) | ||||||
Deferred revenue, current and noncurrent | - | - | - | - | - | (48,580) | 36,265 | (14,802) | (51,404) | 27,195 | 88,673 | (33,231) | ||||||
Contract liabilities | 144,142 | 112,386 | 39,488 | 101,906 | 18,760 | 147,651 | 3,853 | 7,953 | 44,128 | 42,256 | (2,112) | 63,577 | ||||||
Other liabilities | (5,014) | (12,898) | (14,564) | (11,690) | (13,247) | - | - | - | - | - | - | - | ||||||
Operating lease liabilities, current and noncurrent | - | - | - | - | - | (11,427) | (8,296) | (15,482) | (12,164) | (15,067) | (10,536) | (10,106) | ||||||
Other noncurrent liabilities | - | - | - | - | - | (563) | 6,539 | (33) | 167 | (3) | 20 | (81) | ||||||
Net cash provided by operating activities | 1,216,167 | 899,165 | 507,664 | 539,251 | 310,263 | 419,772 | 144,187 | 129,579 | 133,443 | 90,192 | 187,376 | 47,066 | ||||||
Investing activities | ||||||||||||||||||
Purchases of property and equipment | (14,554) | (7,401) | (6,792) | (7,634) | (6,184) | (3,985) | (2,879) | (2,664) | (1,565) | (3,934) | 4,755 | (14,436) | ||||||
Purchases of marketable securities | (2,694,443) | (810,856) | (3,515,282) | (871,511) | (1,704,720) | (1,634,584) | (523,788) | (1,260,327) | (1,854,731) | (626,572) | (2,310,367) | (35,000) | ||||||
Proceeds from sales of marketable securities | - | - | - | - | - | - | - | - | - | - | - | 17,473 | ||||||
Proceeds from sales and redemption of marketable securities | 1,226,056 | 791,533 | 3,707,565 | 302,135 | 350,627 | 1,317,843 | 381,789 | 751,746 | 1,660,032 | 239,407 | 709,459 | 4,619 | ||||||
Purchases of privately-held securities | - | - | (2,924) | (70,000) | - | - | - | - | - | - | - | - | ||||||
Purchases of alternative investments | - | - | - | - | - | - | - | - | - | - | - | - | ||||||
Other investing activities | - | 0 | (1,000) | - | (30,000) | - | (4,000) | - | - | - | - | - | ||||||
Proceeds from sales of alternative investments | - | - | - | - | - | - | - | 0 | - | - | 51,072 | - | ||||||
Net cash used in investing activities | (1,482,941) | (26,724) | 181,567 | (617,010) | (1,390,277) | (320,726) | (148,878) | (511,245) | (196,264) | (391,099) | (1,554,591) | (27,344) | ||||||
Financing activities | ||||||||||||||||||
Principal payments on borrowings | - | - | - | - | - | - | - | - | - | - | - | - | ||||||
Proceeds from the exercise of common stock options | 4,858 | 4,899 | 25,638 | 28,617 | 66,584 | 170,337 | 16,030 | 83,840 | 50,556 | 90,349 | 25,924 | 24,567 | ||||||
Repurchases of common stock | - | - | (19,195) | (18,596) | (17,998) | 18,899 | (17,699) | (9,000) | - | - | - | - | ||||||
Taxes paid related to net share settlement of equity awards | - | - | - | (3,544) | (77,573) | - | - | - | - | - | - | - | ||||||
Other financing activities | 123 | (1,502) | (8) | (27) | 90 | (11) | (306) | 408 | 384 | 335 | 59 | (576) | ||||||
Net cash provided by (used in) financing activities | 4,981 | 3,397 | 6,435 | 6,450 | (28,897) | 151,427 | (1,975) | 75,248 | 50,940 | 90,684 | 25,983 | 23,991 | ||||||
Effect of foreign exchange on cash, cash equivalents, and restricted cash | 292 | (2,404) | (2,074) | 7,538 | 3,980 | 5,908 | (924) | (4,024) | (258) | (4,531) | 2,676 | (6,129) | ||||||
Net increase (decrease) in cash, cash equivalents, and restricted cash | (261,501) | 873,434 | 693,592 | (63,771) | (1,104,931) | 256,381 | (7,590) | (310,442) | (12,139) | (214,754) | (1,338,556) | 37,584 | ||||||
Supplemental disclosures of cash flow information | ||||||||||||||||||
Cash paid for income taxes | - | - | - | - | - | - | - | - | - | - | 4,992 | (106) | ||||||
Cash paid for interest | - | - | - | - | - | - | - | - | - | - | 0 | - | ||||||
Supplemental disclosures of non-cash investing and financing information: | ||||||||||||||||||
Receivable from the exercise of common stock options included in prepaid expenses and other current assets | - | - | - | - | - | - | - | - | - | - | - | - |